<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>包含关系的margin</title>
	<style>
	#div1 {
		padding:20px 40px;
		background: red;
	}
	#div2 {
		padding: 20px 40px;
		background: green;
		margin: 50px;
	}
	</style>
</head>
<body>
	<div id="div1">1
		<div id="div2">2</div>
	</div>
</body>
</html>